We are studying the biosynthetic enzymes, the in vivo control, and the in vivo function of the polyamines. We have now obtained a mutant of E. coli with an absolute amine requirement for growth, which cotransduces with a specific defect in the S12 protein of the small ribosomal subunit. We are investigating the role of polyamines in protein synthesis in vivo. We have cloned the E. coli gene for adenosylmethionine decarboxylase into PBR322, restricted it, and prepared a stable, high copy number plasmid. We have purified the enzyme and have found 1 mole of the cofactor pyruvate per mole of enzyme subunit. We are studying the mechanism of formulation of this unusual cofactor. We have prepared a stable plasmid coding for the adenosylmethionine synthetase of E. coli and prepared large amounts of this enzyme for x-ray crystallography. This reaction requires 1 monovalent and 2 divalent cations. For our studies on the control of amine synthesis in yeast, we have purified ornithine decarboxylase and obtained antibodies to it. We have shown that a post-translational modification is involved in the control of this enzyme.